Such gripper heads are equipped with weft thread clamping means located near the forward gripper head tip. The clamping means usually comprise a fixed clamping pad cooperating with a lever operated movable clamping pad arranged opposite the fixed clamping pad.
In the known gripper head the movable clamping pad is secured to the free leading or forward end of the gripper head by means of a tiltable lever supported on the body of the gripper head. This tiltable lever is operatively connected with a control cam or lever which controls the opening and closing movement of the clamping mechanism, or rather, of the movable clamping pad of the clamping mechanism. The control cam or lever is mounted in the machine frame and operates the tilting lever, whereby the leading end of the weft thread can be gripped between the movable and stationary or fixed clamping pads at the tip of the gripper head. The tiltable lever is spring biased.
One problem with conventional gripper heads of this type resides in the fact that they have a relatively large mass causing respective high inertia forces when these gripper heads are used in looms, especially high speed looms. Such inertia forces limit the operational speed of the loom and also the useful life of the loom components, especially movable loom components because inertia forces increase the wear and tear.
The gripper heads are the last link, so to speak, in the entire drive chain. Therefore, the gripper heads influence the entire drive chain in accordance with the gripper head mass. As a result, all components in the drive chain must be dimensioned in accordance with the requirements dictated by the mass of the gripper heads. It is therefore desirable to make the gripper heads as light as possible, while still assuring their intended purpose. A light gripper head makes it possible to use lighter components throughout the drive chain. Thus, the gripper rod may be of lighter construction, which in turn permits a lighter drive wheel and so forth.